Basic disazo indazolium dyestuffs



United States Patent ABSTRACT OF THE DISCLOSURE This invention concernsbasic disazo dyestuffs having one of the general formulae:

U Y OH floaaaag V Z alk-N CH lTIe x all:

and

Y U OH Z V N/ \C H all,

wherein U and V each represent a member selected from the groupconsisting of the hydrogen atom and the methyl and methoxy groups, Y andZ each represent a member selected from the group consisting of hydrogenand chlorine atoms and the methyl, methoxy and nitro groups, alkrepresents a member selected from the group consisting of the methyl andethyl groups and X6 represents a monovalent anion.

The present invention concerns improvements in and relating to new basicdisazo dyestuffs.

In particular it relates to new dyestuffs of the general formula:

alkyl-N CH No X alkyl in which R represents a hydroxybenzene-azobenzeneradical of the formula:

or a benzene-azobenzene of the formula:

"ice

the nucleus A being able to be substituted by a chlorine atom or amethyl, alkoxy or nitro group, the nucleus B being able to besubstituted by alkyl or alkoxy groups, the alkyl groups in the N or Npositions of the indazole nucleus are groups of low molecular weight,preferably methyl or ethyl groups, and X represents a monovalent anion.

The dyestuffs of Formula I in which R represents ahydroxybenzene-azobenzene residue of Formula a which for convenience weshall refer to as dyestuffs of Formula Ia, may be prepared in severaldifferent ways.

A preferred method comprises coupling the diazo derivative of asubstituted aniline of the formula HrN- A N with a1,Z-dimethyl-6-hydroxy-indazolium salt in aqueous alkaline solution. InFormula II, Y represents a nitro or acylamino group, and the possiblesubstituents of the nucleus A are the same as before.

There is thus obtained a monoazo dyestuff of the formula:

alkyl 1 1 X HC/ N-alkyl OH (II The group Y can be converted into anamino group by reduction or hydrolysis by known processes, the aminoazocompound thus obtained is diazotised, and the diazo derivative formed iscoupled with the coupling compound pling compound H &OH

The azo compound obtained is subjected either to a careful reduction orto hydrolysis, according to known processes, in order to convert thegroup Y into an amino group. The aminoazo compound (IV) thus prepared isdiazotized and the diazo derivative is coupled with a1,2-dialkyl-6-hydroxyindazolium salt in aqueous alkaline solution. Thereaction mixture is then made acid in order to isolate the disazodyestuff of Formula Ia.

A third method of preparation of the dyestuffs of Formula Ia comprisessubjecting the disazo dyestuffs of the formula:

N 110 NH to the action of alkylating agents, possibly in the presence ofanhydrous organic solvents.

Suitable alkylating agents are, for example, the alkyl halides, dialkylsulphates and alkyl ary-lsulphonates. Solvents which may be used are,for example, benzene, toluene, xylenes, chlorobenzene,o-dichlorobenzene, nitrobenzene, chloroform and dimethyl formamide. Thedyestuffs of Formula V may be prepared by coupling diazo derivatives ofthe dyestuffs of Formula IV with 6-hydroxyindazole in aqueous alkalinemedium. It is also possible to couple the diazo derivative of a base ofFormula II with 6-hydr0xy-indazole, in aqueous alkaline medium, to formthe azo compound of formula:

reduce or hydrolyse the group Y, diazotise the aminoazo compound thusobtained and couple this diazo derivative with the phenolic couplingcompound defined above.

A fourth method of preparation of the dyestuffs of Formula Ia comprisesmaking the quaternary compounds of the dyestuffs of Formula VI under thesame conditions as the dyestuffs of Formula V. Dyestuffs of Formula IIIare thus obtained and one then proceeds as in the first method describedabove.

The dyestuffs of Formula I in which R represents a benzene-azobenzeneresidue of Formula b which for convenience we will refer to as dyestuffsof Formula Ib may be advantageously obtained by coupling, an aqueoussolution, 1,2-dialkyl-6-hydroxy-indazolium salts with the diazoderivative of the compound of formula:

(VII) in which the possible substituents of the nuclei A and B are thesame as before.

The dyestuffs of Formula Ib can also be prepared by making thequaternary compounds, as described above, of the disazo dyestuffs of theformula:

HN C H (VIII) themselves prepared by coupling the diazo derivative ofthe dyestufis of Formula VII with 6-hydroxy-indazole.

The dyestuffs of Formula I which are generally very soluble, possess thetinctorial properties of basic dyestufis but are of particular interestfor dyeing fibers of acrylonitrile polymers or copolymers, to which theyimpart full-bodied shades, which are very even and fast, especially tolight and to subsequent shaping treatments. The range of shades obtainedextends from bright orange to bordeaux, passing through scarlet and moreor less brownish reds.

The association between fibre and dye may be represented by the scheme:fibre indazolium azo dye.

In the following examples, which are purely illustrative and to whichthe invention is not restricted, the parts are parts by weight unlessthe contrary is indicated.

Example 1 25 parts of N-monoacetyl p-phenylenediamine are dissolved in200 parts of water and 30 parts by volume of 10 N hydrochloric acid. Thesolution is cooled to 5 C. and a solution of 7 parts of sodium nitritein 50 parts of water is added. At the end of 20 minutes, the solution ofthe diazo derivatives is introduced into a solution of 20 parts of1,Z-dimethyl-6-hydroxy-indazolium chloride in 200 parts of water. Themixture is stirred and dilute ammonia is progressively added untilslight alkalinity is obtained (pH about 7 to 8). When the diazoderivative has disappeared, the precipitate is filtered off, brieflyrinsed, drained and made into a paste in 140 parts of 5 N hydrochloricacid. The mixture is refluxed for an hour and then allowed to cool. Theintermediate amino dyestufi crystallises, and is filtered off, drainedand dried at about 70 C. to C. Weight obtained: 24 parts.

16 parts of this dyestutf are dissolved in 250 parts of water. 12.5parts by volume of 10 N hydrochloric acid are added, the mixture cooledto 5-10 C., and diazotised by the introduction of a solution of 3.5parts of sodium nitrite in 10 parts of water. After stirring for half anhour, 8.5 parts of crystalline sodium acetate are added to the solutionof the diazo derivative, then this solution is introduced into 50 partsof water containing 5 parts of phenol and 5 parts of 10 N caustic soda.Then ammonia is gradually introduced until the pH is about 7 to 8. Thecoupling process is rapidly completed. The reaction mixture is heated to5060 C. and made acid by the addition of hydrochloric acid. Aftercooling, it is filtered and the product drained and dried in an oven.Dry weight: 20 parts.

A solution of 0.5 part of this dyestufi in 200 parts of water isprepared, and 2 parts of acetic acid at 60 g. per litre and 0.5 part ofa condensation product of castor oil with ethylene oxide are added.parts of fibres based on acrylonitrile polymer are introduced at 50 C.,and the bath is taken progressively to boiling point and maintained atthis for an hour and a half. A full-bodied orangebrown shade isobtained, which has excellent general fastness, especially to light.

Example 2 29 parts of the dyestuif obtained by coupling the diazoderivative of 2 chloro 4 amino N acetylaniline with phenol are heatedunder reflux for 2 hours in a mixture of 200 parts of water and 100parts by volume of concentrated hydrochloric acid. The mixture isallowed to cool, and the precipitate is filtered off and then made intoa paste in 300 parts of water and 25 parts by volume of 10 Nhydrochloric acid, and diazotised by the addition of a solution of 7parts of sodium nitrite in 30 parts of water at a temperature of 5-10 C.After stirring for half an hour the diazo derivative is introduced intoa solution of 20 parts of 1,Z-dimethyl-6-hydroxy-indazolium chloridedissolved in 200 parts of water. The mixture is stirred and madeslightly alkaline (pH about 7 to 8) by the slow addition of ammonia.When the coupling is completed, the reaction mixture is heated to 5060C. and made acid by the addition of hydrochloric acid. It is allowed tocool, and the precipitate is filtered off, drained and dried in an oven.The dyestuif obtained dyes fibres based on polymers or copolymers ofacrylonitrile a red-brown shade having excellent general fastness.

A number of other analogous examples are summarised in the followingtable. The position of the substituents of the nucleus A is according tothe numbering given by the Formula a.

Bordeaiix brown. Red brown.

3-methoxyphenol. Ph

Do. D0. Do. Do. Brick red. Orange brown. Bordeaux. Violet browm. .do Do.18 do Do. 19 2-ehloro-5-methoxy. Red brown. 20.- ..do Butt brown. 21..Do. 22.. Do. 23.. Do. 24.. Brown red. 25 Red brown. 26 Do. 27 Do. 28..Do. 29.. m-( resol Do. 30.. -Cresol Orange brown. 31 0.... m-Cresnl D0.32 2-methyl Phenol Do. 33.. n o-Cresol Red brown.

rn-Cresol Do. 2,5dimethyl-phenol. Do. 2.6-dimethyl-phenol. Do. o-OresolDo. 38 -.do...- m-Cresol..-- D

do-- 2,5-dimethylpheriol.

o. Chocolate brown.

40 :do 2,6-dimethylphenol Red brown.

Example 41 14.3 parts of arnino-azobenzene are carefully made into apaste in 50 parts of water and 24 parts by volume of 195 B hydrochloricacid. 450 parts of water and crushed ice are added and the substance isdiazotised at 0.5 C. by the addition in a period of minutes of asolution of 5.2 parts of sodium nitrite in parts of water.

The mixture is stirred for an hour, a little insoluble material isfiltered off, and the filtrate is mixed with a solution of 16.8 parts of1,2-dimethyl-6-hydroxy-indazolium chloride in 200 parts of water. Then17 parts by volume of concentrated ammonia are slowly added so as tobring the pH to about 8. The diazo derivative has completely reacted.The solid is filtered oii, rinsed With a 5% solution of sodium chloride,drained and dried at 50-60 C. 28.3 parts are thus obtained of a dyestuffwhich gives, on polyacrylic fibres, a bright, full-bodied orange shade,which is very even and has remarkable fastness, especially to light.

A number of examples analogous to the above are summarised in thefollowing table.

Ex. R-NH; Shades on acrylic fibers 42 3-methyl-4-phenylazc-anilineBrownish orange.

3-nitro-4-phenylazo-aniline-... Orange gold.4-nitro-4-phenylazo-aniline-. Orange.

Orange brown.

58 2-methyl-4-phenylazo-2-methoxy-5- Bordeaux.

meth yl-aniline.

59 3-methyl-4-phenylazo-2-methoxy-5- Do.

methyl-aniline.

60 4'-methyl-4-phenylazo-2-meth0xy-5- Do.

methyl-aniline.

61 3-nitro--phenylazo-Q-methoxy-5- D0.

meth yl-aniline.

62 4-nitrc-4-phenylazo-2-rnethoxy-5- Do.

methyl-aniline.

We claim: 1. Basic disazo dyestuffs having one of the general formulae:

U Y OH -4 -N=N-N=N- v z alk-N CH NeB X ail:

and

Y U OH 2 v N/ /CH aik wherein U and V each represent a member selectedfrom the group consisting of the hydrogen atom and the methyl andmethoxy groups, Y and Z each represent a member selected from the groupconsisting of hydrogen and chlorine atoms and the methyl, methoxy andnitro groups, alk represents a member selected from the group consistingof the methyl and ethyl groups and X represents a monovalent anion.

2. [4-hydroxy-benzene1-(1 azo 4)-[benzene]-(1 azo 7)-[N N'dimethyl-o-hydroxy-indazolium] chloride.

3. [4-hydroxy-benzene]-(1 azo 4)-[benzene]-(1 azo 7)-[N ,N-diethyl-6-hydroxy-indazolium] chloride.

4. [4-hydroxy-benzene]-(1 azo 4)-[2-methylbenzene]- l1 azo 7)-[N ,N-dimethyl-6-hydroxy-indazolium] chlori e.

5. [4-hydroxy-benzene1-(1 azo 4)-[2-methylbenzene]- (1 azo 7)-[N N-diethyl-6-hydroxy-indazolium] chloride.

6. 7-(benzene azo benzene azo)-6-hydr0xy-N ,N dimethyl-indazoliumchloride.

7. 7- (benzene azo benzene azo)-6-hydroxy-N ,N diethyl-indazoliumchloride.

